This invention relates generally to the art of books and more specifically, to books having mechanisms mounted thereon for stiffening them when they are placed in open configurations. In a sense, this invention relates to the art of lap desks.
A difficulty many people have when using books, especially lose-leaf notebooks, is that front and back flap covers of the books usually rotate freely about hinge seams so that such books are cumbersome when held open in a lap. Similarly, it often occurs that loose-leaf notebooks, when open, extend laterally beyond small work surfaces of desks used in many schools so that front and rear flaps thereof rotate downwardly, offering little or no support for loose-leaf papers in the notebooks. When one works with a loose-leaf notebook on his lap or at a small desk, rear and front flat covers provide little or no support but rather rotate easily about hinge seams beyond a common plane in which they are approximately parallel one with the other.
U.S. Pat. No. 5,037,136 to McIntire discloses a book stiffener for preventing front and rear flap covers from rotating substantially beyond a common plane in which they are approximately parallel with one another. This book stiffener basically includes an elongated, rigid, rotatable strip attached to an outside surface of the book cover by a swivel attachment which allows the rotatable strip to rotate between a stiffening position in which it extends across hinge seams of front and rear flap covers for preventing the front and rear flap covers from rotating substantially beyond the common plane and a disabled position in which it extends more nearly parallel with a back binding so that it does not extend across the hinge seams. Although this book stiffener has proven to be useful, it has the problem that the rotatable strip tends to rotate when it should not. This makes the book stiffener awkward to use and negates some of the usefulness of the book stiffener.
Thus, it is an object of this invention to provide a book stiffener of the type disclosed by McIntire in U.S. Pat. No. 5,037,136, but which has stable fixed positions of its rotatable strip, and yet its rotatable strip can be easily rotated when desired between the stiffening and disabled positions.
Similarly, it is an object of this invention to provide such a book stiffener which is inexpensive to construct, easy to mount on a book and uncomplicated to use.